A diplomatic dispute is brewing between China and the United States over Iran's nuclear programme. Beijing is set to block any new United Nations sanctions.
The United States is convinced that Iran is trying to develop nuclear weapons and there are calls for new sanctions to try and stop it, the ABC reports.
But China's ambassador to the United Nations, Zhang Yesui, says "more time and patience" is needed to find a diplomatic solution.
China can veto any new UN sanctions.
Chinese companies that sold missile technology to Iran are supposed to be subject to US trade sanctions but an American non-governmental organisation, the Wisconsin Project on Nuclear Arms Control, has uncovered widespread trade between banned Chinese companies and the US.
American officials are now investigating the front companies that conducted the trade.